<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title></title>
</head>
<body>

</body>
</html>

<script>
	// var num1 =10;
	// var num2 =20;
	// alert("num1="+num1+";"+"num2="+num2);
	// var temp = num1;
	// num1=num2;
	// num2=temp;
	// alert("num1="+num1+";"+"num2="+num2);

	var num = 9;
	if ("abc") {
		alert("num是一个偶数");
	}else{
		alert("num是一个奇数");
	}
</script>